Environment-friendly high-flame-retardance special instrument shielding control cable

Abstract

The utility model relates to the technical field of control cables, in particular to an environment-friendly high-flame-retardant shielding control cable for special instruments, which comprises a plurality of mutually twisted control wire cores. The plurality of flame-retardant filling strips are filled in gaps among the control wire cores and are wrapped and fixed by a flame-retardant belt to form a cable core with a circular cross section; the outer wall of the cable core is coated with the composite shielding layer; and the outer sheath is extruded on the outer wall of the composite shielding layer. Through the combination of the copper strip shielding layer and the copper wire shielding layer in the composite shielding layer, respective advantages can be exerted on different frequency bands, a comprehensive shielding effect is provided, meanwhile, the elastic deformation space is increased by utilizing the convex structure of the copper strip, the overall flexibility of the cable is high, wiring in frequent bending and narrow space is facilitated, and the cable has a wide application prospect. And meanwhile, the aramid fiber braid layer is utilized to buffer and protect the copper wire braid layer, so that the probability that the copper wires are broken under the action of compression / tensile stress of the cable can be reduced, and the shielding performance of the cable is maintained.

Description

Technical Field

[0001] This utility model relates to the field of control cable technology, and more specifically to an environmentally friendly, highly flame-retardant shielded control cable for special instruments. Background Technology

[0002] Shielded control cables are mainly used for signal transmission in industrial fields, especially for wiring electrical instruments and control signal transmission in automated control systems, to achieve stable signal transmission and ensure the monitoring and safe operation control of electrical equipment.

[0003] Shielded control cables typically consist of a conductor, an insulation layer, a shielding layer, and a sheath. The conductor is usually made of high-purity copper or aluminum to ensure good conductivity. The insulation layer uses materials with high insulation and flame-retardant properties, such as cross-linked polyethylene or halogen-free flame-retardant polyolefins, to isolate the conductor and prevent current leakage and short circuits. The shielding layer is a critical part of the cable and is usually made of metallic materials such as copper foil, aluminum foil, or metal braided mesh. Its function is to shield against external electromagnetic interference and ensure stable signal transmission within the cable.

[0004] Currently, the most common shielding layer is copper wire braided shielding to maintain the cable's good flexibility and space laying. However, the wire breakage rate will increase after repeated bending, and it cannot provide sufficient shielding effect in complex electromagnetic environments. At the same time, a single shielding layer cannot provide effective flame retardancy, especially in the application of special electrical appliances and special instruments where flame retardancy, shielding and high mechanical performance are required. Utility Model Content

[0005] To address the technical problems existing in shielded control cables in the prior art, this utility model proposes an environmentally friendly, highly flame-retardant shielded control cable for special instruments, comprising:

[0006] Multiple control wire cores twisted together;

[0007] Multiple flame-retardant filler strips are filled in the gaps between the control wire cores and the cable core with a circular cross-section is wrapped and secured by flame-retardant tape.

[0008] A composite shielding layer is wrapped around the outer wall of the cable core;

[0009] The outer sheath is extruded onto the outer wall of the composite shielding layer;

[0010] The composite shielding layer includes an inner shielding layer, a buffer layer, and an outer shielding layer distributed from the inside out. The inner shielding layer includes a copper strip covering layer with a raised structure on the surface of the copper strip. The buffer layer includes an aramid braided buffer layer, and the outer shielding layer includes a copper wire braided shielding layer.

[0011] Preferably, the copper strip cladding layer includes a longitudinally wrapped copper strip shielding layer.

[0012] Preferably, the raised structure on the surface of the copper strip is distributed in a matrix or honeycomb pattern.

[0013] Preferably, the height of the protrusion structure is 1 to 2 times the thickness of the copper strip.

[0014] Preferably, the diameter of the protrusion is 1.5 to 2 mm, and the spacing between adjacent protrusions is 2 to 3 times the diameter of the protrusion.

[0015] Preferably, the weave density of the aramid braided buffer layer is greater than the distribution density of the raised structure.

[0016] Preferably, the aramid braided buffer layer includes aramid filaments intersecting each other along a first direction and along a second direction, wherein the first direction is parallel to the cable axis and the second direction is perpendicular to the cable axis.

[0017] Preferably, the braiding angle of the copper wire braided shielding layer is 45 degrees, and the braiding density is greater than 85%.

[0018] Preferably, the flame-retardant filler strip comprises a low-smoke halogen-free flame-retardant polypropylene filler strip.

[0019] Preferably, the outer sheath comprises an environmentally friendly, low-smoke, halogen-free, flame-retardant sheath.

[0020] Based on the above technical solutions, the significant advantages of this utility model's environmentally friendly, highly flame-retardant shielded control cable for special instruments are:

[0021] The environmentally friendly, highly flame-retardant shielded control cable for special instruments proposed in this utility model provides comprehensive shielding through the combination of copper tape shielding layer and copper wire shielding layer in the composite shielding layer. At the same time, the raised structure of the copper tape increases the elastic deformation space, improves the overall flexibility of the cable, and is beneficial for wiring in frequent bending and confined spaces. Meanwhile, the aramid braided layer buffers and protects the copper wire braided layer, reducing the probability of copper wire breakage under the pressure / tensile stress of the cable, and maintaining the shielding performance of the cable. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the environmentally friendly, highly flame-retardant shielded control cable for special instruments, as shown in this utility model.

[0023] Figure 2 This is a schematic diagram of the cross-sectional structure of the environmentally friendly, highly flame-retardant shielded control cable for special instruments, as shown in this utility model.

[0024] Figure 3 This is a schematic diagram of the composite shielding layer shown in this utility model. Detailed Implementation

[0025] Combination Figure 1 As shown, the environmentally friendly, high flame-retardant special instrument shielded control cable of this utility model embodiment includes a cable core, a composite shielding layer and an outer sheath 7. The cable core has seven control wire cores 1 arranged in a 1+6 configuration. Each control wire core 1 uses a high-purity oxygen-free copper conductor and a halogen-free flame-retardant polyolefin insulation layer.

[0026] Multiple flame-retardant filler strips 2 are filled in the gaps between the control conductors 1 and the cable core, which is circular in cross-section, is wrapped and secured by flame-retardant tape. The flame-retardant filler strips 2 are preferably low-smoke halogen-free flame-retardant polypropylene filler strips.

[0027] Thus, using low-smoke halogen-free flame-retardant polypropylene filler strips between control cores 1 provides excellent flame-retardant effect. At the same time, it produces less smoke and releases no toxic gases when burning, meeting environmental protection standards. It is also lightweight, reducing the overall weight of the cable.

[0028] Furthermore, the cable core is wrapped with double-layer mica tape to form a flame-retardant wrapping layer 3. Mica tape is a high-performance flame-retardant wrapping tape with excellent high-temperature resistance and flame-retardant properties.

[0029] In high-temperature or fire conditions, mica tape can form an insulating protective layer to prevent the spread of flames and heat transfer, ensuring that the cable continues to work normally for a certain period of time. At the same time, mica tape itself is non-toxic and odorless, meeting environmental protection standards.

[0030] Furthermore, a composite shielding layer covers the outer wall of the cable core.

[0031] The composite shielding layer includes an inner shielding layer 4, a buffer layer 5, and an outer shielding layer 6 distributed from the inside out. The inner shielding layer 4 includes a copper strip covering layer with a raised structure 41 on the surface of the copper strip. The buffer layer 5 includes an aramid braided buffer layer, and the outer shielding layer 6 includes a copper wire braided shielding layer.

[0032] A three-layer composite shielding layer is adopted. The surface of the copper strip is provided with a raised structure 41 and an aramid braided layer to provide buffering, which provides elastic deformation space for the cable during bending. The raised structure 41 and the aramid braided layer can absorb and buffer some stress, avoiding stress concentration on the copper wire braided shielding layer, thereby reducing the possibility of copper wire breakage due to stress concentration.

[0033] Meanwhile, the aramid braided layer has high strength and flexibility, which can evenly distribute the stress generated when the cable is bent throughout the entire shielding structure. This reduces the stress on each copper wire in the copper wire shielding layer, lowering the risk of a single copper wire breaking due to excessive force.

[0034] In a preferred embodiment, the copper strip cladding layer includes a longitudinally wrapped copper strip shielding layer. Thus, the longitudinally wrapped copper strip shielding layer can improve the cladding speed.

[0035] Optionally, the raised structures 41 on the surface of the copper strip are distributed in a matrix or honeycomb pattern. The regularly distributed raised structures 41 facilitate roll forming on the surface of the copper strip using tools.

[0036] In an optional embodiment, the height of the protrusion 41 is 1 to 2 times the thickness of the copper strip. Specifically, the diameter of the protrusion 41 is 1.5 to 2 mm, and the spacing between adjacent protrusions 41 is 2 to 3 times the diameter of the protrusion 41.

[0037] By designing a roll forming die of appropriate size, copper strip can be roll forming a copper strip with regularly distributed protrusions 41. The copper strip is then longitudinally wrapped to form an inner shielding layer 4. The protrusions 41 on its surface can support the aramid braided layer and increase the deformation space.

[0038] Furthermore, the braiding density of the aramid braided buffer layer is greater than the distribution density of the raised structures 41. In this way, the aramid braided buffer layer can be supported by multiple raised structures 41, forming a buffer space for deformation and compression.

[0039] Furthermore, to ensure good support of the copper wire braided shielding layer for the aramid braided buffer layer, the aramid braided buffer layer includes intersecting aramid filaments along a first direction and a second direction, wherein the first direction is parallel to the cable axis and the second direction is perpendicular to the cable axis. The braiding angle of the copper wire braided shielding layer is 45 degrees, and the braiding density is greater than 85%.

[0040] In this way, the copper wire braided shielding layer can be placed on the outer layer of the aramid braided buffer layer and is elastically supported by the crisscrossing aramid fibers to disperse the stress it experiences when bending.

[0041] In addition, the addition of an aramid braided buffer layer can improve the overall mechanical strength of the cable and enhance its ability to resist external forces such as tension, compression and abrasion. This makes the cable have a long service life in complex operating environments. Because aramid materials have good temperature resistance and flame retardant properties, they can delay the spread of fire and reduce the damage to the cable in the event of a fire.

[0042] Preferably, the outer sheath 7 is extruded onto the outer wall of the composite shielding layer. The outer sheath 7 can be an environmentally friendly, low-smoke, halogen-free, flame-retardant sheath. For example, a low-smoke, halogen-free polyolefin sheath possesses environmentally friendly characteristics, flame-retardant properties, and good mechanical properties. It is also resistant to aging and has good resistance to ultraviolet radiation, oxygen, and heat, thus extending the service life of the cable.

[0043] In conjunction with the above embodiments, this application provides a comprehensive shielding effect through the combination of copper tape shielding layer and copper wire shielding layer in the composite shielding layer. At the same time, the raised structure of the copper tape increases the elastic deformation space, improves the overall flexibility of the cable, and is beneficial for wiring that requires frequent bending and is located in confined spaces. Meanwhile, the aramid braided layer buffers and protects the copper wire braided layer, which can reduce the probability of copper wire breakage under the pressure / tensile stress of the cable and maintain the shielding performance of the cable.

[0044] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this invention shall be determined by the claims.

Claims

1. An environmentally friendly, highly flame-retardant shielded control cable for special instruments, characterized in that, include: Multiple intertwined control wire cores (1); Multiple flame-retardant filler strips (2) are filled in the gaps between the control wire cores (1) and the cable core with a circular cross section is wrapped and secured by flame-retardant tape. A composite shielding layer is wrapped around the outer wall of the cable core; The outer sheath (7) is extruded onto the outer wall of the composite shielding layer; The composite shielding layer includes an inner shielding layer (4), a buffer layer (5), and an outer shielding layer (6) distributed from the inside out. The inner shielding layer (4) includes a copper strip covering layer, and the surface of the copper strip is provided with a raised structure (41). The buffer layer (5) includes an aramid braided buffer layer, and the outer shielding layer (6) includes a copper wire braided shielding layer. The braiding density of the aramid braided buffer layer is greater than the distribution density of the raised structure (41). The aramid braided buffer layer includes aramid filaments intersecting each other along a first direction and along a second direction, wherein the first direction is parallel to the cable axis and the second direction is perpendicular to the cable axis.

2. The environmentally friendly, high flame-retardant shielded control cable for special instruments according to claim 1, characterized in that, The raised structure (41) on the surface of the copper strip is distributed in a matrix or honeycomb pattern.

3. The environmentally friendly, high flame-retardant shielded control cable for special instruments according to claim 1, characterized in that, The copper strip cladding layer includes a longitudinally wrapped copper strip shielding layer.

4. The environmentally friendly, high flame-retardant shielded control cable for special instruments according to claim 1, characterized in that, The height of the protrusion structure (41) is 1 to 2 times the thickness of the copper strip.

5. The environmentally friendly, high flame-retardant shielded control cable for special instruments according to claim 1, characterized in that, The diameter of the protrusion structure (41) is 1.5~2mm.

6. The environmentally friendly, highly flame-retardant shielded control cable for special instruments according to claim 1 or 5, characterized in that, The spacing between adjacent protrusions (41) is 2 to 3 times the diameter of the protrusion (41).

7. The environmentally friendly, high flame-retardant shielded control cable for special instruments according to claim 1, characterized in that, The braided copper wire shielding layer has a braiding angle of 45 degrees and a braiding density of more than 85%.

8. The environmentally friendly, high flame-retardant shielded control cable for special instruments according to claim 1, characterized in that, The flame-retardant filler strip (2) includes a low-smoke halogen-free flame-retardant polypropylene filler strip.

9. The environmentally friendly, high flame-retardant shielded control cable for special instruments according to claim 1, characterized in that, The outer sheath (7) includes an environmentally friendly, low-smoke, halogen-free flame-retardant sheath.

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